This invention relates to an electronic cash register concurrently designed to provide tax information.
Generally, commodity taxes assessed on articles sold by a supermarket are paid by buyers indirectly through the supermarket to a competent taxation office. In this case, a cashier has personally to figure out tax amount or read a tax amount from a tax table for each transaction, thus rendering tax calculation time-consuming and leading to the registration of an erroneous tax amount.
For resolution of the above-mentioned difficulties, there has been developed an electronic cash register concurrently designed to figure out a tax amount. Such electronic cash register contains a memory stored with a tax table shown, for example, in Table 1 below indicating taxable amounts and assessable taxes.
Table 1 ______________________________________ Tax Table Taxable Amount From To Assessable Taxes $ .cent. $ .cent. .cent. ______________________________________ 1 12 0 13 34 1 35 59 2 60 87 3 88 1 12 4 1 13 1 37 5 1 38 1 62 6 1 63 1 87 7 1 88 2 12 8 2 13 2 37 9 2 38 2 62 10 2 63 2 87 11 ______________________________________
As seen from Table 1 above, taxable amounts ranging from 1.cent. to 87.cent. are divided into four groups having unequal amount differences. Taxable amounts ranging from 88.cent. to 1$ 87.cent. are divided into four groups having an equal amount difference of 25.cent.. Larger taxable amounts are similarly divided into four groups differentiated from each other by the same rate of 25.cent.. Namely, taxable amount are increased by 1$ for every four groups. Accordingly, assessable taxes are raised by 1.cent. for each group of taxable amounts. With Table 1 above, taxable amounts lying between 1.cent. and 87.cent. are collectively referred to as an unequally differentiated section. Taxable amounts lying between 88.cent. and 1$ 87.cent. are collectively referred to as a first equally differentiated section. Thus, taxable amounts ranging from N$ 88.cent. to (N+ 1)$ 87.cent. are collectively referred to as an equally differentiated section of the (N+ 1) order.
For calculation of assessable taxes, it is advised to store a memory with data given in Table 1 above, specifically the maximum taxable amount of each group of the unequally differentiated section; an assessable tax on each maximum taxable amount; the maximum taxable amount of each group of the respective equally differentiated sections; a tax assessable on each maximum taxable amount in the equally differentiated section; the maximum taxable amount A (87.cent. in this case) of the unequally differentiated section; a number of groups (4 in this case) of which each equally differentiated section is formed; a difference W (1$ in this case) between the amounts of every adjacent equally differentiated sections, and cause a data-processing circuit to carry out upon depression of tax keys an arithmetic operation expressed by the following equation from the contents of the memory: EQU TA- A= C (1)
where TA denotes a taxable amount and C shows the result of an arithmetic operation. Where C represents zero or a negative value, then a tax assessable on the taxable amount TA is determined only from the unequally differentiated section of the tax table of Table 1.
Where C determined by the equation (1) above has a positive value, for example, where TA is 4$ 80.cent. and C is 3$ 93.cent., then the following equation is used to judge that the corresponding taxable amount belongs to the equally differentiated section of the (N+ 1) order. EQU (C/W)- 1.ltoreq. N&lt; C/W (2)
Obviously N is a positive integer. The value of N is arrived at by repeatedly subtracting W from C until the result of the subtraction shows a negative value and subtracting 1 from a count denoting how many times the subtraction was carried out. Where C is, for example, 3$ 93.cent., then N is 3. Thus a taxable amount of 4$ 80.cent. is shown to belong to the fourth equally differentiated section.
A total number of groups E of all the equally differentiated sections lying before that equally differentiated section to which a subject taxable amount belongs can be determined by the following equation: EQU N.times. T=E (3)
since N is 3 and T is 4 in the above-mentioned case, E is 12. As seen from Table 1 above, an assessable tax is increased by 1.cent. for each group. Therefore, a tax assessable on a taxable amount W.times.N== 3$ is formed to be 12.cent..
That portion F of a taxable amount TA whose assessable tax has not been figured out is expressed by the following equation: EQU TA-W.times.N= F (4)
Thus F is determined to be 4.80- 3= 1$ 80.cent. which falls within the range set forth in Table 1. Accordingly, a tax G assessable on said 1$ 80.cent. is determined to be 7.cent. from Table 1. In the above-mentioned case, therefore, a total tax K assessable on the taxable amount TA is determined to be 12+ 7= 19.cent..
If provided with a memory stored with data for calculating an assessable tax and an arithmetic operation program, then a cash register can concurrently indicate a total amount of articles sold and a tax assessable thereon.
However, a commodity tax on a taxable amount is subject to change, for example, by amendment of the taxation law. Therefore, a memory has to be stored with fresh data for calculating an assessable tax each time need arises. Consequently, demand has been made to develop an electronic cash register which enables tax-calculating data to be easily stored in a memory each time and can also examine readily whether any fresh tax-calculating data has been correctly stored in the memory. Further in same cases, a prescribed tax rate is applied to a larger taxable amount than a maximum taxable amount (for example, 1$ 87.cent.) belonging to the first equally differentiated section. Therefore, it has also been desired to develop an electronic cash register concurrently usable with such fixed rate taxation system.